As connector of the above mentioned type, there is an electrical connector which comprises a plug connector and a receptacle connector, each a connector half, intermatable with each other for electrical connection. The plug connector includes a longitudinal row of plug contacts, each plug contact extending vertically in a plug-contact retaining portion of an electrically insulative housing. The receptacle connector includes a longitudinal row of receptacle contacts, each receptacle contact extending vertically in a receptacle-contact retaining portion of an electrically insulative housing.
In this electrical connector, either the plug contacts or the receptacle contacts are provided with resiliency for the purpose of maintaining a contact pressure necessary for each respective pair of plug and receptacle contacts to be held in electrical connection while the plug connector and the receptacle connector are intermated. In this case, usually the other group of contacts, i.e., plug contacts or receptacle contacts, which are not provided with resiliency are formed each in an ordinary plate and are retained each as is in the contact retaining portion of the respective housing.
However, these contacts which are applied in a plate form are inherently subjected to dimensional deviation in the fabrication process and inaccurate positioning in the assembly process. As a result, some of the contacts may be unintentionally positioned, extruding outward or being relieved out of the respective contact-retaining grooves of the contact-retaining portion. If the connector half assembled in such fault condition is mated with the other connector half, then such contacts in relief can be deformed. To avoid this problem of unintentional or accidental deformation, a design is proposed in which each of the contacts of a concerned connector half is provided with an engaging portion so that this engaging portion engages with a respective contact-retaining groove to keep the respective contact in a correct position without giving it any relief or extrusion.
As an example of such construction, each of the contacts 160 of a respective connector half is formed with a fattened "T" figure in cross section, and each corresponding contact-retaining groove 154 is formed likewise to receive this contact fittingly as shown in FIG. 10. In this design, however, it is difficult to provide a sufficient strength to extruding portions 155 which are formed at the opening of each of the contact-retaining grooves 154 for the purpose of withholding the pressurized insertion and of maintaining the pressurized retention of a respective contact 160. As a result, this design inherently has the problem of insufficient retainability of the contacts in the insulative housing.
FIG. 11 shows another design. Each of the contact-retaining grooves 254 is formed with a trapezoidal cross section, and each respective contact 260 is likewise formed with a trapezoidal cross section, correspondingly, so that the contacts 260 are press fit into the respective contact-retaining grooves 254, thereby being retained in the housing.
However, this design requires much quality control work in the production stage because it is difficult to maintain correct lengths for the upper and lower sides and correct angles for the slopes of the trapezoids, all of which factors are important for the contacts 260 to be press fit smoothly into and retained securely in the contact-retaining grooves 254. Thus, the difficulty involved in the fabrication of the contacts 260 and the grooves 254 makes this design infeasible.